1. Field
The present invention relates generally to communications, and more specifically, to adaptive control of transmission procedures.
2. Background
Wireless communication systems are designed to allow multiple users to share a common communications medium. One such wireless communications system is a code division multiple access (CDMA) system. The CDMA communications system is a modulation and multiple access scheme based on spread-spectrum communications. In a CDMA communications system, a large number of signals share the same frequency spectrum and, as a result, provide an increase in user capacity. This is achieved by transmitting each signal with a different code that modulates a carrier, and thereby, spreads the signal over the entire spectrum. The transmitted signals may be separated in the receiver by a demodulator using a corresponding code to de-spread the desired signal. The undesired signals, whose codes do not match, contribute only to noise.
In recent years, wireless communication devices have been used to access various packet based networks such as the Internet and the like. A common example is a laptop computer connected to a cellular telephone that accesses the Internet through a wireless CDMA network. In these and similar applications, the wireless communications device may establish and maintain a network connection over an air traffic channel with a radio network within the wireless CDMA network. Once the network connection is established, it is usually maintained even if the air traffic channel is torn down during periods of inactivity. By maintaining the network connection, bandwidth may be saved that would otherwise be needed to reestablish a network connection once packet transport resumes. The network connection that exists in the absence of an air traffic channel is referred to as a dormant connection.
When the network connection is dormant, various overhead channels may be used to determine when packets are ready to be transported between the wireless communications device and the packet based network. When data is ready to be transported, a new air traffic channel may be established between the wireless communications device and the radio network. A new air traffic channel, however, tends to consume valuable wireless resources that are needed to support various functions such as power control, handoff and channel allocations. Short data bursts may not require these functions because the data is not continuous, and is usually sent only once in a predetermined time period. Accordingly, it would be advantageous to enable short data burst communications using existing overhead channels without having to establish an air traffic channel between the wireless communications device and the radio network.